Never thought I'd find this in a million years---but on eBay, here is an old 1982 ad for Sigmas---and my SE-19 looks exactly like the one lying on it's side in the ad (in front of the other guitars):
http://cgi.ebay.com/ws/eBayISAPI.dll?VISuperSize&item=380271828800

(If that link doesn't work, hopefully this one will--just hit the "enlarge" to see the pic: http://cgi.ebay.com/1982-MARTIN-SIGMA-DM-3M-DR-41-GUITAR-PRINT-AD-/380271828800?pt=Guitar_Accessories&hash=item5889f79f40 ) If the auction ends before anyone sees this photo, and the photo is no longer visible, I'll figure another way of getting a link on here so this ad can be seen and you'll see what my guitar looks like.

This is the very first picture I have ever seen of a guitar identical to mine that wasn't mine! :)